Reception system for receiving objects

ABSTRACT

A reception system for receiving objects comprises at least one reception device for receiving objects, a conveyor device, which has at least one conveyor belt section for conveying objects in a conveyance direction in the at least one reception device, and a sensor device, which is arranged on the at least one reception device, for detecting objects in the at least one reception device. It is provided in this case that the sensor device is designed to emit sensor signals along different signal paths over the reception device, to conclude a fill level of the reception device on the basis of an interaction of at least one of the sensor signals with objects conveyed into the reception device. In this manner, a reception system for receiving objects is provided, which enables further automation, in particular in the conveyance of objects into a reception device.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to European Patent Application No.15190452.1 filed on Oct. 19, 2015, the entirety of which is incorporatedby reference herein.

BACKGROUND

The invention relates to a reception system for receiving objects and amethod for operating such a reception system.

Such a reception system can be designed, for example, as a packingtrough system for a product checkout system. However, such a receptionsystem can fundamentally also be designed, for example, as a reversevending machine (RVM in short), in which containers in the form ofbeverage containers subject to deposit are collected, for example, on abottle placement table in a reverse vending region.

Such a reception system for receiving objects comprises at least onereception device for receiving objects, a conveyor device, which has atleast one conveyor belt section for conveying objects in a conveyordirection in the at least one reception device, and a sensor device,which is arranged on the at least one reception device, for detectingobjects in the at least one reception device.

Reception devices exist, for example, in the form of product checkoutsystems, in which the detection and registration of products for paymentcan take place substantially automatically for a customer. Such aproduct checkout system, for example, at a supermarket cash register,comprises a conveyor device, on which a customer can place objects andwhich conveys the objects into the region of a scanning device. At thescanning device, the products are scanned and detected and registered,for example, on the basis of identification codes attached to theproducts, such as barcodes or the like. After passing the scanningdevice, the products are then conveyed into the region of a receptiondevice in the form of a packing trough, from which the customer canremove the products and can pay at a payment device.

At such a reception system in the form of a product checkout system, theoperation is to be made as simple as possible for a customer—if possiblewithout assistance by operating personnel—and should be able to beperformed intuitively. For this purpose, in conventional productcheckout systems, for example, sensors are arranged on conveyor beltsections of the conveyor device, which detect whether, for example,products have been placed on a conveyor belt, so that depending thereon,the conveyor belt can be started and the products can be conveyed intothe region of a scanning device.

In addition, the desire exists for further automation, for example, forthose systems which comprise multiple reception devices and in which anobject separation device, for example, in the form of a pivotabledistributing guide, is to be adjusted to guide objects into one or theother reception device. Currently, such distributing guides are usuallyadjusted by hand by operating personnel, which process can be subject toerror and requires additional operating steps.

SUMMARY

An object of the present invention is to provide a reception system forreceiving objects and a method for operating such a reception system,which enable further automation, in particular when conveying objectsinto a reception device.

This object is achieved by a subject matter having the features asdescribed herein.

The sensor device is accordingly designed to emit sensor signals alongdifferent signal paths over the reception device, in order to conclude afill level of the reception device on the basis of an interaction of atleast one of the sensor signals with objects conveyed in the receptiondevice.

The present invention proceeds from the concept of measuring the filllevel at a reception device by means of a sensor device. This is basedon the concept that items of information can be obtained via the filllevel, which can be used to control a reception system, for example, tocontrol the conveyance speed of conveyor belt sections of the conveyordevice or to adjust a distributing guide for guiding objects todifferent reception devices on the basis of the fill level.

To determine the fill level at a reception device, it is provided thatthe sensor device emits sensor signals along different signal paths overthe reception device. The sensor device therefore spans the receptiondevice at least in sections with a network of sensor signals, whichinteract with objects located in the reception device, for example, inthat signal paths are interrupted and/or sensor signals are reflected ordeflected. On the basis of interrupted signal paths or on the basis ofreflected signals, a conclusion can then be drawn about the degree towhich the reception device is filled, so that at least a (coarse)estimated value can be ascertained for the fill level of the receptiondevice.

The sensor signals represent signals of infrared light, for example. Thesensor device therefore emits, for example, by means of an infrared LED,infrared light along different signal paths and receives the infraredlight at different receivers, for example, formed by photodiodessensitive in the infrared, so that it can be detected on the basis ofthe received signal whether objects are located in the signal path ofthe infrared light or not.

In this context, it is to be noted that the sensor device canfundamentally also use other types of sensors, for example ultrasonicsensors, capacitive sensors, inductive sensors, pressure sensors,cameras, or the like, and is thus not restricted to sensors for emittingand/or receiving infrared light.

In one advantageous embodiment, the sensor device has a plurality ofsensor units, which are arranged distributed about the reception device.

In a first variant, for this purpose, for example, one sensor can beprovided which emits sensor signals. The sensor signals are received viaa plurality of receivers arranged distributed about the receptiondevice, wherein the emitter can emit identical sensor signals, so thateach receiver receives the same sensor signal, or the emitter can alsoemit individual sensor signals, which are each uniquely assigned to onereceiver, so that each receiver receives an individual sensor signaluniquely assigned thereto.

In a second variant, a plurality of emitters can also be provided foremitting sensor signals, wherein these sensor signals are received by ashared receiver. In this case, the sensor signals emitted by thedifferent emitters can differ from one another, so that the receiver candifferentiate the sensor signals of the different emitters and canassociate each of them uniquely with an assigned emitter. In anothervariant, it is also possible that the individual emitters emitsequentially in a chronologically staggered manner, for example in shortcycles, so that the receiver always only receives one signal from asingle emitter at a specific point in time.

A combination of the first and the second variants is also conceivableand possible for this purpose. Thus, a plurality of emitters and aplurality of receivers can be provided, wherein each emitter emits aplurality of sensor signals, which are received by a plurality ofreceivers, so that one emitter emits sensor signals to multiplereceivers and one receiver receives sensor signals from multipleemitters.

Because emitters and receivers are distributed around the receptiondevice, the reception device can be spanned with a network of signalpaths. In a state in which the reception device is empty, the sensorsignals can propagate unobstructed between the emitters and thereceivers and are received at the receivers. However, if objects arelocated in the reception device, at least some of the signal paths arethus interrupted or (significantly) damped (for example, at edges or ontransparent objects) or are even amplified under certain circumstances(due to bundling of the light signal, for example on transparent objectsas a result of a lens effect, for example on curved surfaces), so thatall sensor signals are no longer received at all receivers or at least adeviation in the received signal strength from an expected signalstrength occurs, which can be analyzed accordingly to determine the filllevel.

A reception device is, in one specific embodiment, bordered by wallsections, which are arranged in a box shape in relation to one another,for example, to form a rectangular reception device. Sensor units of thesensor device are arranged spatially offset on these wall sections, sothat different signal paths are formed between the different sensorunits, along which sensor signals are transmitted.

In one concrete exemplary embodiment, a first sensor unit, which formsan emitter, can be arranged on a first wall section of the at least onereception device, and a second sensor unit, which forms a receiver, canbe arranged on a second wall section, which is opposite to the firstwall section, such that the second sensor unit is opposite to the firstsensor unit. The first sensor unit therefore emits a sensor signal fromthe first wall section in the direction of the second sensor unit on theopposing, second wall section. If the sensor signal is received at thesecond sensor unit, this means that no products are located between thefirst sensor unit and the second sensor unit in the reception device. Incontrast, if the signal path is interrupted by a product and accordinglyno sensor signal is received at the second sensor unit, it can thus beconcluded that the reception device is filled (at least) up to thesignal path between the first sensor unit and the second sensor unit.

The opposing arrangement of sensor units corresponds to an arrangementsimilar to a light barrier. It is conceivable and possible in this casethat both sensor units both emit sensor signals and also receive sensorsignals, so that signals are emitted both from the first sensor unittoward the second sensor unit and also, vice versa, signals are emittedfrom the second sensor unit toward the first sensor unit.

In principle, signal paths can extend in a direct optical connectionbetween an emitter and a receiver. However, it is also conceivable andpossible in this case that a signal path forms via a reflection point(or multiple reflection points), in that a sensor signal is emitted byan emitter, reflected at a reflection point, and only then received by areceiver.

It is additionally conceivable and possible that a sensor unit isdesigned as a reflection sensor for emitting a sensor signal and forreceiving a reflected signal. A separate, spatially separated receiveris therefore not assigned to the emitter, but rather the sensor unit isdesigned to emit sensor signals and to detect possibly reflected signalcomponents. By means of such reflection sensors, not only can it beascertained (in the manner of a light barrier), whether a signal path isinterrupted, but rather the reflected signals per se can be studied withrespect to the signal strength thereof, for example, to conclude thedistance to an object at which the sensor signal has been reflected, forexample.

For example, signals reflected at such a reflection sensor can beassigned to a short range and a long range of the sensor. The signallevel of a received reflected signal can thus be compared to differentthreshold values, to determine on the basis of this threshold valuecomparison whether an object at which the sensor signal has beenreflected is located at short range or long range to the sensor. If thesignal level of the received reflected signal exceeds a first thresholdvalue assigned to the short range of the sensor, for example, it can beconcluded therefrom that the reflected object is located at the shortrange to the sensor. In contrast, if the signal level of the reflectedsignal is between the first threshold value and a second, lowerthreshold value, it can be concluded therefrom that the reflectiveobject is located at long range to the sensor. If the reflected signalis weaker than the second threshold value, it can thus be presumed thatit is not a signal reflected on an object, but rather an interferencesignal or the like.

Sensors in the form of ultrasonic sensors can advantageously be used forthe measurement and analysis of reflection signals, in the case of whichdifferent reflection properties of objects only play a subordinate role.The measurement and analysis of such reflection signals using othersensors is also fundamentally conceivable and possible, however.

Such a reflection measurement can additionally be used, for example, ina reception system in the scope of a reverse vending machine, in whichit is to be ascertained at a reception device, for example, to whatextent the reception device is filled with containers in the form ofbottles or cans. Bottles, for example, have at least approximatelysimilar reflection properties, so that the distance to a sensor can beconcluded on the basis of the strength of different reflection signals(an assignment to a short range or long range can at least beperformed).

It is also conceivable and possible in one embodiment that the receptionsystem has at least one sensor unit, which is designed as a reflectionsensor for emitting a sensor signal and for receiving a reflected signaland is additionally designed for receiving an emitted signal of anothersensor device. The sensor unit is therefore, on the one hand, areflection sensor but is also used, on the other hand, as a receivingsensor unit, for example, in the scope of a one-way light barrier, inwhich a sensor signal is emitted by a sensor unit and is received byanother sensor unit. In this manner, on the one hand, it can berecognized in the scope of a light barrier function whether an object isarranged at all on a route between an emitting sensor unit and areceiving sensor unit. In addition, an item of distance information canalso be obtained by the reflection sensor, so that it can be determinedat which location (approximately) the object is located on this route.

The reception system for example comprises a control device, which isconnected to the different sensor units of the sensor device andcontrols the operation of the sensor units. The analysis device thusactivates the sensor units of the sensor device to emit sensor signalsand receives sensor data from the sensor units, which have been obtainedon the basis of received (or non-received) sensor signals. The controldevice can then perform an analysis on the basis of the sensor data, toconclude the fill level of the reception device.

For example, if a signal path between an emitter and a receiver isinterrupted by an object located on the reception device andaccordingly, when the emitter emits a sensor signal, no sensor signal isreceived at the assigned receiver, this can thus be analyzedaccordingly. Because the positions of the sensor units on the receptiondevice are known and therefore the signal paths between the differentemitters and receivers are also known, the fill level can be concludedfrom the interruption of one or more signal paths or from the receptionof reflected signals from different regions of the reception device, sothat at least an estimated value can be specified for the fill level.

For example, it can be ascertained by suitable sensor distributionwhether the reception device is empty, 25% filled, 50% filled, 75%filled, or full (100% filled). Fill level ranges of the reception deviceare thus differentiated on the basis of the signal paths, so thatsuccessive filling of the reception device with objects can bemonitored.

A control of the reception system can be performed on the basis of thefill level. Thus, the conveyance speeds of one or more conveyor beltsections of the conveyor device can be adapted as a function of the filllevel. If it is established in this case that a reception device isnearly full, the conveyance speed of a conveyor belt section whichconveys objects into the reception device can thus be reduced, to reducethe speed at which objects are guided into the reception device. It isalso conceivable to start another conveyor belt section, to enable theguiding of objects toward another reception device.

It is also conceivable that an object separation device in the form of adistributing guide on the reception device is controlled as a functionof the fill level. The control device can thus be designed to activate adrive device for adjusting the object separation device as a function ofan ascertained fill level, for example if it is recognized that thereception device is nearly full and therefore objects are to be guidedinto another reception device. The object separation device in the formof the distributing guide can be arranged so it is pivotable on thereception device, for example. If it is recognized that the receptiondevice is full or at least nearly full, the object separation device isthus pivoted and therefore the conveyor path toward the reception deviceis blocked, to guide objects along the object separation device towardanother reception device.

In addition, the control device can be designed to output items ofinformation to a user about the fill level at a reception device. Theuser can thus be informed, for example, about whether a reception deviceis completely full, nearly full, or empty. Additionally oralternatively, it can be output via the control device whether areception device, for example, a packing trough in a packing troughsystem, is occupied by a customer or is free.

In addition, it is possible to select a reception device automaticallyby means of the control device. Thus, the control device, for example inthe case of a packing trough system, in which multiple packing troughs,for example more than two packing troughs, are present, canautomatically select a new packing trough when a previously used packingtrough is full and is therefore not ready to receive further objects.

A scenario for providing an intelligent reception device is alsoconceivable, for example an intelligent packing trough, in which objectsare intentionally guided to a location, at which a user removes objectsfrom the reception device, by means of a suitable conveyor device. Sucha location can be detected by the sensors, for example, because a freeregion results at this location in the reception device, which can bedetected by sensors. If this is the case, one or more conveyor deviceson the reception device can be activated in a targeted manner to feedobjects toward this free region. This is advantageously usable forexample in a packing trough system, in which a user removes productsfrom a packing trough.

In the case of a reception system for a reverse vending machine, forexample, it is conceivable and possible to adapt dynamic sortingsubregions as a function of the fill level, thus to make them wider ornarrower. A statement can also be made if necessary about containers ofone bottle type located in a sorting region, so that users are informedbeforehand about how many bottles are available in a specific sortingregion, so that beverage crates can be provided in a suitable number,for example.

In one advantageous embodiment, the sensor units of the sensor deviceeach have a display device, for example in the form of one or more LEDs,for outputting visual display signals as a function of a fill level ofthe reception device. If a reception device is ready to receive objects,the sensor units of the sensor device can thus light up green at thereception device, for example, to signal the readiness of the receptiondevice. If the fill level of the reception device has exceeded apredetermined threshold value, the display device can thus change itscolor from green to orange, so that it is signaled to a user and alsothe operating personnel that the reception device is approaching itsfull state. If one switches over to another reception device byadjusting the object separation device, the display devices of thesensor units can thus change their color to red, to indicate that thereception device is not ready to receive objects.

In a further advantageous embodiment, it can be provided that sensorunits of the sensor device mutually identify one another. For thispurpose, signals can be exchanged between the sensor units, for example,in a chronologically staggered manner, by way of which the sensor unitscan mutually recognize whether and in what number and at which locationother sensor units are provided. For example, a sensor unit designed asan emitter can emit a sensor signal which contains an identificationidentifier which identifies the emitter, for example in the form of adigital bit sequence or the like, and is used as a test signal. Thesensor signal can be received by a receiver, so that the emitter can beidentified at the receiver and it can be recognized that an exchange ofsensor signals is possible between the emitter and the receiver in thecorrect manner.

An identifying signal can be, for example, a simple bit sequence, forexample comprising five pulses having different high or low values (1and 0). However, an identifying signal can also be an addressidentifier, for example, the MAC address or a dynamically assigned ID,for example.

Such identifying sensor signals can be exchanged in this case betweenall emitters and receivers, so that the sensor units receive items ofinformation via each of the signals, for example about the distance andvisibility (optionally also via reflection points) of other sensorunits. In this case, a unique identification identifier can be assignedto each emitter, which is transmitted in the scope of the exchangedsensor signals, so that an emitter can uniquely identify itself inrelation to a receiver. However, this is not required.

Such a recognition of the sensor units among one another can optionallyalso take place indirectly, for example so that a first sensor unitrecognizes another, second sensor unit via an interposed third sensorunit, which transmits signals between the first and the second sensorunits in an intermediary manner.

Such a mutual identification can be carried out in a calibration passbefore the actual operation, to teach the system. In addition, however,it can also be provided that identification identifiers are alwaysexchanged repeatedly in operation between the different emitters andreceivers, so that the operational readiness of the system can bechecked in a repetitive manner.

This procedure also makes it possible to recognize soiling ormanipulation attempts on the system. The sensor device can thus bedesigned to analyze a test signal received at a receiver and to comparethe signal level of this test signal to a stored reference value. Achange at the sensor device can then be concluded on the basis of thecomparison. If the receiver is soiled, for example, and the signal levelof the received test signal is thus lower, this can thus be recognizedaccordingly. The signal level of the test signal will also change(increase or decrease), if the position of the receiver is changed inrelation to the emitter, which can also be recognized accordingly on thebasis of the comparison to the reference value.

A degree of soiling can be recognized on the basis of differentthreshold value steps, for example. A gradually occurring soiling can belearned in this case by way of a cyclic query in running operation andtherefore can be taken into consideration or can trigger a readjustment.It can be differentiated therefrom whether a manipulation takes place ona sensor unit, because in this case a sudden change occurs, for examplein the signal strength or the signal runtime (for example, in the caseof ultrasonic signals).

Cleaning of sensors can be executed, for example, by starting a cleaningprogram in a system menu.

The reference value can be initially determined in this case, forexample by calibration before putting into operation on the basis of thereceived signal level in the starting state. If deviations from thisreference signal level result in later operation, this indicates achange on the system.

In one embodiment, a product checkout system has a reception system ofthe above-described type. In such a product checkout system, thereception system can be embodied, for example, by a packing troughsystem having one or more packing troughs. The reception system cancontain in this case, for example, a scanning device for (automatically)scanning and registering objects. By means of the conveyor device,objects are guided past the scanning device, registered therein, andguided toward a reception device in the form of one or more packingtroughs of the reception system.

However, it is also conceivable and possible that the reception systemis a component of a reverse vending machine, in which a user introducesan object subject to deposit and the reception system is used to collectintroduced objects subject to deposit.

The object is also achieved by a method for operating a reception systemfor a reception system. In the method, at least one reception devicereceives objects, in that a conveyor device having at least one conveyorbelt section conveys objects in a conveyance direction into the at leastone reception device. A sensor device, which is arranged on the at leastone reception device, detects objects in the at least one receptiondevice. It is provided in this case that the sensor device emits sensorsignals along different signal paths over the reception device, toconclude a fill level of the reception device on the basis of aninteraction of at least one of the sensor signals with the objectsconveyed into the reception device.

Advantages and advantageous embodiments, as have been described abovefor the reception system, are also applied similarly for the method, sothat reference is made to the above statements.

BRIEF DESCRIPTION OF THE DRAWINGS

The concept on which the invention is based will be explained in greaterdetail hereafter on the basis of the exemplary embodiments illustratedin the figures.

FIG. 1 shows a top view of one exemplary embodiment of a productcheckout system.

FIG. 2 shows a schematic view of a packing trough having a sensor devicearranged thereon.

FIG. 3 shows a schematic view of another exemplary embodiment of apacking trough having a sensor device arranged thereon.

FIGS. 4A-4E show views of an exemplary embodiment of a packing troughsystem, during filling of a packing trough.

FIGS. 5A-5D show views of another exemplary embodiment of a packingtrough system, during filling of a packing trough.

FIG. 6 shows a schematic flow chart for teaching a sensor device of thepacking trough system.

FIG. 7 shows a schematic view of a packing trough system having a sensordevice arranged thereon.

FIGS. 8A-8C show a schematic view of sensor units of a sensor device indifferent spatial location relationships.

FIG. 9 shows a schematic view of an arrangement of sensor units of asensor device on a packing trough.

FIG. 10 shows a schematic view of another exemplary embodiment of asensor device on a packing trough.

FIG. 11 shows a schematic view of a control device for controlling thesensor units.

FIG. 12 shows a schematic view of an exemplary embodiment of theinterconnection of the sensor units.

DETAILED DESCRIPTION

A reception system is described hereafter on the basis of exemplaryembodiments of a packing trough system in a product checkout system.However, this is to be understood solely as an example. Fundamentally, areception system of the type described here can also be used in othersystems, for example in reverse vending machines or monitoring systems,in which a fill level is to be monitored on a (planar) reception devicefor receiving objects.

FIG. 1 shows a schematic top view of an exemplary embodiment of aproduct checkout system 1, which can be used, for example, at asupermarket cash register for detecting and registering products forpayment by a customer.

The product checkout system 1 has a conveyor device 2 having multipleconveyor belt sections 20, 21, 22, 23, 24. A customer can place productson a first conveyor belt section 20 in this case. Via this firstconveyor belt section 20, the products are conveyed through a scanningdevice 3, to detect the products automatically in the scanning device 3and, for example, to register them on the basis of bar codes attached tothe products. From the first conveyor belt section 20, the productsarrive on a second conveyor belt section 21 and, along a conveyor pathP, via a third conveyor belt section 22, on a conveyor belt section 23,which is assigned to a packing trough 40 of a packing trough system 4.The products collect in the packing trough 40, so that the products canin turn be removed by the customer and can be packaged to be carried,for example. Finally, the customer can pay for the products at a paymentdevice 5.

The packing trough system 4 has multiple packing troughs 40, 41 (in theillustrated exemplary embodiment two packing troughs 40, 41). Thepacking troughs 40, 41 are separated from one another by a productseparation device 42 in the form of a product distributing guide,wherein this product distributing guide 42 can be adjusted to guide theproducts into one or the other packing trough 40, 41.

In the product checkout system 1, the products are conveyed in aconveyance direction F through the scanning device 3 to a respectivereception-ready packing trough 40, 41. The receiving packing trough 40,41 is filled successively until all products of a customer have beenregistered and supplied to the packing trough 40, 41. The productseparation device 42 is thereupon rearranged so that subsequent productsof another customer are guided toward another packing trough 40, 41.

During filling of a packing trough 40, 41, it may occur that the packingtrough 40, 41 reaches its maximally filled state, for example becausethe speed at which the products are conveyed into the packing trough 40,41 is greater than the speed at which a customer removes products fromthe packing trough 40, 41. If this is not recognized, a furtherconveyance of products toward the packing trough 40, 41 can occur,although the packing trough 40, 41 is actually full, which can result ina backup of products on the conveyor device 2.

To enable a control of the product checkout system 1 as a function ofthe fill level of the packing trough 40, 41, in the present case, asensor device 6 is therefore arranged on the packing trough 40, 41,which is used to monitor the fill level of the packing trough 40, 41.

FIG. 2 shows a first exemplary embodiment of such a sensor device 6 on apacking trough 40 of a packing trough system 4. In the sensor device 6,a plurality of sensor units 601-609 are arranged on different wallsections 400-403 of the packing trough 40, spatially distributed aroundthe packing trough 40. The wall sections 400-403 delimit the packingtrough 40 in a box shape and therefore represent outer walls of thepacking trough 40.

In the illustrated exemplary embodiment, sensor units 601-609 areprovided, which emit sensor signals S along different signal paths overthe packing trough 40 and therefore span the packing trough 40 at leastin sections with a network of signal paths. The sensor units 601-609 canbe used in this case as an emitter and/or as a receiver and aretherefore designed for emitting sensor signals S and/or for receivingsensor signals S.

In the illustrated exemplary embodiment, the sensor 601, which isarranged on the front wall section 400—observed along the conveyancedirection F—of the packing trough 40 emits sensor signals S, which arereceived by multiple sensor units 602-608 designed as receivers. Thesensor 601 can emit identical sensor signals S in this case, so thateach receiving sensor 602-608 receives the same sensor signal S.Alternatively, it is conceivable that the sensor 601 emits differentsensor signals S, wherein an individual sensor signal S is uniquelyassigned to each receiver 602-608.

In addition, in the exemplary embodiment according to FIG. 2, pairs ofsensor units 601-609 are formed, which mutually transmit sensor signalsS. Thus, the sensor 606 is assigned to the sensor 601, wherein thesensors 601, 606 each emit a sensor signal S and receive the sensorsignal S emitted from the respective other sensor 606, 601. The sensorunits 601, 606 are located opposite to one another in this case, onopposing wall sections 400, 402.

In addition, the sensor 609 is assigned to the sensor 602 and the sensor608 is assigned to the sensor 605. The sensors 602, 609 or 605, 608,respectively, are opposite to one another in pairs on the wall sections401, 403 and exchange sensor signals S in pairs, so that each sensor602, 609, 605, 608 emits a sensor signal S which is received by therespective other sensor 609, 602, 608, 605 and vice versa.

Another exemplary embodiment is shown in FIG. 3. In this exemplaryembodiment, three sensors 611, 612, 613, which are embodied asreflection sensors, are arranged on a wall section 403 of the packingtrough 40. The sensors 611-613 each emit a sensor signal S, which isreflected on a product object 7 located in the packing trough 40 (in thecase of the sensors 611, 612) or on the opposing wall 401 (in the caseof the sensor 613). In the case of the sensors 611, 612, the presenceand if necessary also the distance of a product object 7 in the packingtrough 40 can be concluded by analyzing the reflected signal componentsreceived at the sensors 611, 612. In the case of the sensor 613, it canbe recognized whether a product object 7 interrupts the signal pathbetween the sensor 613 and the opposing reflection point 62, to concludethe presence of a product object 7 on the basis of this interruption.

The sensors 611, 612 are so-called reflection scanners, which analyzethe reflection on the product object 7 themselves. By analyzing whethera reflected signal is received at the sensor 611, 612, the presence of aproduct object 7 can therefore be concluded.

The sensor 613, in contrast, is a reflection light barrier, whichanalyzes whether a light beam reflected at a reflection point 62 isinterrupted by a product object 7. In this case, for example, it can bedifferentiated whether a reflected signal received at the sensor 613 hasbeen caused by a reflection on the product object 7 or on the reflectionpoint 62, in that a polarization of the reflected signal takes place onthe reflection point 62.

The functionality for detecting a fill level will be explained hereafteron the basis of FIGS. 4A to 4E for the exemplary embodiment according toFIG. 2 and on the basis of FIGS. 5A to 5D for the exemplary embodimentaccording to FIG. 3.

In the exemplary embodiment according to FIGS. 4A to 4E, a plurality ofsensor units 601-610 are arranged on each of two adjacent packingtroughs 40, 41 of a packing trough 4. This exemplary embodiment issimplified in this case in relation to the exemplary embodimentaccording to FIG. 2 such that one sensor unit 601, 606 is used as theemitter of sensor signals S for each packing trough 40, 41, while theremaining sensor units 602-605 or 607-610, respectively, are used asreceivers. By means of the signal paths S2-S5 formed between thedifferent sensor units 601-610, each packing trough 40, 41 is spanned atleast in sections like a network, to conclude the fill level of therespective packing trough 40, 41 on the basis of an interaction ofproduct objects 7 with the sensor signals S.

In the starting state according to FIG. 4A, the product separationdevice 42, which is arranged so it is pivotable about a pivot axis 420on the wall 403 separating the packing troughs 40, 41, is located in aposition in which the lower packing trough 40 in FIG. 4A is accessible,but the adjacent, other packing trough 41 is blocked in the conveyancedirection F. Therefore, products which are conveyed via the conveyorsection 22 toward the packing troughs 40, 41 strike the productseparation device 42 and are guided toward the packing trough 40 andtherefore conveyed into the packing trough 40.

In the starting state according to FIG. 4A, the packing trough 40 isempty. No product objects 7 are located in the packing trough 40.Accordingly, the sensor signals S emitted by the sensor 601, which isused as the emitter, are received by the sensor units 602-605, which areused as receivers. The signal paths S2-S5 formed between the sensorunits 601-605 are not interrupted.

If the packing trough 40 fills, because products 7 are conveyed into thepacking trough 40, as shown in FIG. 4B, firstly the signal path S5formed between the sensor unit 601 and the opposing sensor 605 isinterrupted. The sensor units 601-610, as schematically illustrated inFIG. 2, are connected to a control device 43, which generates sensordata on the basis of the sensor signals S received at the sensor units602-605 and analyzes these data for the fill level determination. If itis determined by means of the control device 43 that signal path S5 isinterrupted (but not the remaining signal paths S2-S4), it is thusconcluded that the packing trough 40 is filled approximately 25%.

If the packing trough 40 fills further, as shown in FIG. 4C, the signalpath S4 between the sensor unit 601 used as the emitter and the sensor604 used as the receiver is thus next interrupted, which is recognizedand analyzed by the control device 43. The control device 43 concludestherefrom that the packing trough 40 is approximately 50% filled.

If the packing trough 40 fills further, the signal path S3 between thesensor unit 601 and the sensor unit 603 is thus interrupted next, asshown in FIG. 4D, from which the control device 43 concludes that thepacking trough 40 is approximately 75% filled.

Finally, as shown in FIG. 4E, the signal path S2 between the sensor unit601 and the sensor unit 602 is also interrupted, from which the controldevice 43 concludes that the packing trough is 100% filled.

In the filled state according to FIG. 4E, all signal paths S2-S5 areinterrupted. At the fill level of 75% (FIG. 4D), the signal paths S3-S5are interrupted; at the fill level of 50% (FIG. 4C), the signal paths S4and S5 are interrupted. In order that a specific fill level isrecognized, it is necessary for all preceding signal paths (for example,for the fill level 75%, in addition to the signal path S3, also thepreceding signal paths S4, S5) to be interrupted. In this manner, adifferentiation is made between a (brief) interruption of a signal pathS2-S5 when conveying a product object 7 into the packing trough 40 andthe actual successive filling of the packing trough 40.

The recognition of the fill level can be used for a control of theconveyor device 2. Thus, it can be provided that the conveyance speed ofthe conveyor belt section 22 and also other conveyor belt sections 20,21, 23, 24 is controlled as a function of the fill level of the packingtrough 40. It can thus be provided that the conveyance speed of theconveyor belt section 22 is set to a maximum in the case of emptypacking trough 40 (FIG. 4A) and in the case of 25% filled packing trough40 (FIG. 4B). If the fill level of 50% (FIG. 4C) is reached, the controldevice 43 can activate the conveyor belt section 22 to reduce theconveyance speed, so that the conveyor belt section 22 is now onlydriven at half conveyance speed, for example. If the packing trough 40is full (FIG. 4E), the conveyor belt section 42 can finally be stopped.

In addition, the product separation device 42 can also be activated as afunction of the fill level. It can thus be provided, as shown in FIG.4E, that in the case of full packing trough 40, the control device 43activates a drive device 44 of the product separation device 42, topivot the product separation device 42 about the pivot axis 420 andtherefore block the packing trough 40 and to make the other, adjacentpacking trough 41 accessible for receiving products. Products conveyedvia the conveyor belt section 22 are therefore guided into the packingtrough 41 along the conveyance path P, which is now oriented into thepacking trough 41.

Display devices 64 in the form of light-emitting diodes or the like canbe provided on the sensor units 601-610 (see FIG. 4A). These displaydevices 64 can be used to display different states of the packingtroughs 40, 41.

The sensor units 601-610 can additionally or alternatively also beconnected to external display devices, via which signaling can beperformed. In addition, it is also possible to perform signalingspatially separated from the sensor units 601-610, for example, in thatsuitable actuators are activated or signaling is performed via a centralcontrol unit, for example a display screen of the central control unit.

It can thus be provided that in the state according to FIG. 4A, thedisplay devices 64 at the sensor units 601-605 of the packing trough 40light up green to signal that the packing trough 40 is ready to receiveproducts. In contrast, the display devices 64 at the other packingtrough 41 can light up red, for example, to indicate that no productscan be conveyed into this packing trough 41. If the packing trough 40fills up to the fill level of 75%, for example, (FIG. 4D), the displaydevices 64 of the sensor units 601-605 of the packing trough 40 can thuschange their color from green to orange, to indicate that the packingtrough 40 has filled to a large extent. Finally, if the packing trough40 is full (FIG. 4E), the display devices 64 of the sensor units 601-605of the packing trough 40 can thus change their color to red, while thedisplay devices 64 of the sensor units 606-610 of the packing trough 41switch to green, to now indicate that the packing trough 41 is ready toreceive products.

The assignment of a fill level value to sensor signals at the individualsensor units 601-605 is illustrated in the following table:

Meaning when Sensor sensor X occupied Control measure 605 Fill level 25%Display devices 64 light up green 604 Fill level 50% Belt speed of theconveyor belt 22 is reduced, display devices 64 light up green 603 Filllevel 75% Belt speed of the conveyor belt section 22 is reduced, displaydevices 64 light up orange 602 Fill level 100% Conveyor belt 22 stops,display devices 64 light up red, product separation device 42 isadjusted to release another packing trough

In the exemplary embodiment according to FIGS. 5A to 5B, four sensorunits 611-618, which implement reflection sensors, are arranged at eachof the packing troughs 40, 41 on an elongated, outer wall section 401.Each sensor 611-618 emits a sensor signal S along parallel signal pathsS1-S4 in this case.

In the starting state according to FIG. 5A, the packing trough 40 isempty and ready to receive products, while the other packing trough 41is blocked by the product separation device 42. In this case no (or onlyweak) reflected signals are received at the sensor units 611-614 of thepacking trough 40.

If the packing trough 40 fills, as shown in FIG. 5B, products 7initially collect in the region of the last sensor unit 614, the signalpath S4 of which is therefore interrupted. A reflection occurs in thiscase at the product objects 7, which is received at the sensor unit 614as a reflected signal.

The sensor units 611-614 each have a short range and a long range. Adifferentiation is made between the short range and the long range onthe basis of the signal level of the reflected signals. If the reflectedsignal is strong and if the signal level of the received, reflectedsignal is greater than a first threshold value, it is thus concludedtherefrom that the reflective product object 7 is located at short rangeto the sensor 611-614. If the signal level of the received, reflectedsignal is less than the first threshold value, in contrast, but isgreater than a second threshold value, it is thus concluded therefromthat the reflective product object 7 is located at long range to thesensor 611-614.

In the state according to FIG. 5B, product objects 7 are located in theregion of the sensor unit 614 such that a reflection takes place atshort range and is detected accordingly at the sensor unit 614. Theupstream sensor unit 613, in contrast, receives a reflected signal atlong range, caused by a product object 7, which is located at long rangeto the sensor 613. It is concluded from this combination that thepacking trough 40 has a fill level between 25% and 50%.

In the state according to FIG. 5C, the sensor units 613, 614 each detectproduct objects 7 at short range. It is concluded therefrom that thepacking trough 40 is 50% filled.

If the packing trough 40 is completely filled, as illustrated in FIG.5D, all sensor units 611-614 thus receive reflected signals at shortrange.

A control of the conveyance direction 2 and a control of the productseparation device 42 can in turn be performed depending on the filllevel, as has been described above for the exemplary embodimentaccording to FIGS. 4A to 4E.

The assignment of a fill level to the reflected sensor signals receivedat the sensor units 611-614 is illustrated in the following table:

Reaction on the basis of the State Meaning Occupied sensors items ofsensor information 1 0%, empty None Display devices 64 light up green 20%-25% Long range sensor 614 Display devices 64 light up green 3 25%Long range and short Display devices 64 light up range sensor 614 green4 25%-50% Long range and short Display devices 64 light up range sensor614, green long range sensor 613 5 50% Long range and short Belt speedof the conveyor range sensor 614, belt section 22 is reduced, long rangeand short display devices 64 light up range sensor 613 green 6 50%-75%Long range and short Belt speed of the conveyor range sensor 614, beltsection 22 is reduced, long range and short display devices 64 light uprange sensor 613, green long range sensor 612 7 75% Long range and shortBelt speed of the conveyor range sensor 614, belt section 22 is reduced,long range and short display devices 64 light up range sensor 613,orange long range and short range sensor 612 8 75%-100% Long range andshort Belt speed of the conveyor range sensor 614, belt section 22 isreduced, long range and short display devices 64 light up range sensor613, orange long range and short range sensor 612, long range sensor 6119 100%, full Long range and short Conveyor belt 22 stops, range sensor614, display devices 64 light long range and short up red, productseparation range sensor 613, device 42 is adjusted to long range andshort release another packing range sensor 612, trough long range andshort range sensor 611

To span a network of sensor units 601-610, as in the exemplaryembodiment according to FIG. 2 or the exemplary embodiment according toFIGS. 4A to 4E, the sensor units 601-610 are assigned to one anothersuch that, for example, N receivers receive sensor signals S from oneemitter. For this purpose, it is necessary that the system is taught,i.e., pairs of sensor units 601-610 are formed, between which signalpaths S2-S5 are spanned.

The teaching can primarily be directed to being able to establish aconnection structure at all between a sensor 601 used as an emitter andthe sensors 602-605 used as receivers in the exemplary embodimentaccording to FIGS. 4A to 4E. A flow chart for this purpose is shown inFIG. 6.

After the start (step A1), firstly an emitting sensor unit 601 isaddressed and requested to emit a sensor signal S to an assignedreceiving sensor unit 602-605 (step A2). The modulation frequency of thesensor signal S is initially set in this case, for example, to a defaultvalue, corresponding to a minimum value of the modulation frequency(step A3). It is now checked whether a connection can be established tothe receiving sensor unit 602-605, i.e., that the receiving sensor unit602-605 receives the sensor signal S from the emitting sensor unit 601(steps A4 and A5). If no connection is established, thus if there is noreception at the receiving sensor unit 602-605, the modulation frequencyis thus increased in the direction of a carrier frequency, for example(step A6).

It is now checked again in steps A4 and A5 whether a connection isestablished. If a connection is established, a tolerance value is addedto the modulation frequency used (step A7), the modulation frequency isstored and used in future for establishing the connection to this sensorunit 602-605 (step A8). The process is then ended (step A9).

Different procedures can be used for emitting the sensor signals S insteps A1 and A2 between an emitting sensor unit 601 and a receivingsensor unit 602-605 and for teaching the system.

For example, if there is a unique assignment between an emitting sensorunit 601 and a receiving sensor unit 602-605, the corresponding assignedports of the control unit 43 are thus activated (see FIG. 2), so thatthe emitting sensor unit 601 emits a sensor signal S, which is receivedby the receiving sensor unit 602-605.

If multiple receivers 602-605 are assigned to one emitter 601, theemitter 601 is thus switched to active mode and emits sensor signals.The receiving sensor units 602-605 are switched to active modesequentially by activating the corresponding ports of the control device43, so that a sensor signal from the emitting sensor unit 601 isreceived sequentially at the receiving sensor units 602-605. The controlunit 43 obtains a signal from one receiving sensor unit 602-605, whichis presently switched to active mode, at one point in time.

If one receiving sensor unit is assigned to a plurality of emittingsensor units, the receiver is thus active while the emitting sensorunits are activated to emit sensor signals sequentially. One signal isthus received from a currently emitting sensor unit at the receivingsensor unit at one point in time.

For example, a frequency of 38 kHz can be used as the default value forthe carrier frequency. The variation of the carrier frequency can beperformed, for example, in steps of approximately 75 Hz. For example, areceiver can have the greatest sensitivity at the default carrierfrequency of 38 kHz, wherein the sensitivity of the receiver can bechanged by variation of the modulation frequency. By intentionallyworsening the sensitivity, a (low) damping, for example, can be set atthe receiver, which enables sensing, for example of transparent objects.

For the sensor units 601-605 to recognize one another, it is onlynecessary per se for the sensor units 601-605 to exchange signals withone another. This can be performed in a chronologically sequentialmanner, as described above. In this case, the sensor signals S do nothave to have a particular form and in particular do not have to containa special identifier.

In order that the sensor units can mutually identify one another, thesensor units 601-610 can however also be provided with a separateaddress in the form of an identification identifier. To mutuallyidentify one another, the sensor units 601-610 can exchange theiridentification codes in this case, which makes possible a uniquerecognition and assignment of the sensor signals S to a specificemitter, so that multiple emitters can also emit their sensor signalssimultaneously in the scope of the teaching. If, controlled by thecontrol device 43, for example in the arrangement according to FIG. 7,the sensor unit 601 is requested to identify itself in relation to theother sensor units 602, 603, the sensor unit 601 emits a test signalwhich contains the identifier of the emitting sensor unit 601. Thereceiving sensor units 602, 603 can therefore uniquely identify theemitting sensor units 601 on the basis of the received test signal,wherein different signal propagation paths, for example also indirectpropagation paths are possible by reflection at a wall section 401(signal S′).

Such a test signal can have the form of a bit sequence, for example, inthe scope of which, for example, different pulses are emitted. Thus, asensor signal S can have, for example, three pulses having a length of20 μs each and a high signal level, between each of which pulses havinga pulse length of 35 μs and a low signal level are emitted, so that apulse having a high signal level is followed by a pulse having a lowsignal level. A pulse sequence 10101 results.

However, such a test signal can also be a unique ID, for example anaddress identifier such as a MAC address or an ID which is dynamicallyassigned by the control device 43, for example.

The propagation path can simultaneously also be used as a characteristicfor the position determination of the sensor units 601-603. Thus, thesignal level of the received test signals can be analyzed to determinethe distance of the receiving sensor units 602, 603 from the emittingsensor units 601 via this signal level.

It can additionally be recognized by the repeated measurement of testsignals and the signal level thereof whether a change occurs in therelative position of the sensor units 601-603 in relation to oneanother.

This is illustrated in FIGS. 8A to 8C. Thus, a receiving sensor unit602, when it is arranged in the correct location relationship inrelation to an emitting sensor unit 601 (FIG. 8A) will thus receive atest signal having a specific signal level. The receiving sensor unit602 is arranged in this case, for example, inside a main light cone L ofthe emitting sensor unit 601 and accordingly receives a comparativelystrong signal.

If the relative position of the receiving sensor unit 602 in relation tothe emitting sensor unit 601 is changed and the receiving sensor unit602 is displaced, for example, into a scattered light cone L′ of theemitting sensor unit 601 (FIG. 8B), the signal level of the receivedtest signal thus becomes weaker, which can be measured accordingly. Thesignal level of the received test signal also becomes weaker, if thedistance between the emitting sensor unit 601 and the receiving sensorunit 602 increases (FIG. 8C), which can also be recognized accordingly.The spatial location change between the emitter and the receiver canindicate an attempt at manipulation at the sensor device 6, for example.

Such a scattered light cone L′ results, for example, in the case ofinfrared sensors which use infrared LEDs. In general, such infraredsensors have the greatest intensity along their central light axis,which drops outward radially in relation to the light axis. A scatteredlight cone around the central light axis having a cone angle of 35°results, for example.

In addition, the determination of the spatial location relationshipbetween sensor units 601-604 can also be improved by scattered lightmeasurements, as illustrated in FIG. 9. Thus, in the arrangementaccording to FIG. 9, one receiving sensor unit 602, 604 is assigned toeach of the emitting sensor units 601, 603. The emitting sensor unit 601emits a main light cone L1, in which the assigned receiving sensor unit602 is located, and additionally emits a scattered light cone L1′. Theother emitting sensor unit 603 emits a main light cone L2, within whichthe assigned receiving sensor unit 604 is located. In addition, thisemitting sensor unit 603 also emits a comparatively broad scatteredlight cone L2′. The receiving sensor unit 602, which is actuallyassigned to the emitting sensor unit 601, is also located within thisscattered light cone L2′. The receiving sensor unit 602 assigned to theemitting sensor unit 601 therefore also receives scattered light fromthe scattered light cone L2′ of the other emitting sensor unit 603 andcan draw conclusions on the basis of a measurement of the level strengthof this scattered light about the relative location relationship inrelation to the emitting sensor unit 603.

In principle, a single sensor unit can be sufficient to span a networkof different signal paths S2-S6, as shown in FIG. 10. In the exemplaryembodiment according to FIG. 10, one sensor unit 601 emits fivedifferent sensor signals, which propagate on different signal pathsS2-S6 over the packing trough 40 and are guided, by reflection atreflection points 632-637, back to the sensor unit 601 and are receivedthere again. In this case, signal paths are also possible which areguided by multiple reflections back to the sensor unit 601, as in thesignal paths S6 in FIG. 10. The fill level of the packing trough 40 canagain be concluded on the basis of the interruption of a signal pathS2-S7.

For example, the sensor signals emitted by the sensor unit 601 aregenerated on the basis of patterns, which are stored in a database ofthe control device 43. In this manner, different sensor signals can begenerated, which are assigned to the individual signal paths S2-S6. Thesensor signals assigned to the different signal paths S2-S6 can bedifferentiated from one another on the basis of the received lightpulses at the sensor unit 601, for example on the basis of the numberand duration of the light pulses.

FIG. 11 shows a schematic view of a control device 43 for controllingthe system and in particular the sensor units 601-610.

It is to be noted here that a unified control device 43 can be providedto activate the sensor units 601-610 and perform signal processing.However, it is also conceivable and possible to provide different units,which jointly assume controlling functions and are part of the overallsystem at the same time.

In the exemplary embodiment according to FIG. 11, a first control unit430 is provided, which can be implemented by a PC system, for example,and is used, for example, to execute a concrete application of a cashregister system. A second control unit 431, which can be embodied, forexample, as a programmable logic controller (PLC) or also as anelectronic controller and is connected to a third control unit 432, isconnected to this first control unit 430.

The sensor units 601-610 are activated via the third control unit 432,and a first signal analysis of signals which are received by the sensorunits 601-610 also takes place at the third control unit 432, forexample. For example, the third control unit 432, which can be embodiedas an electronics board, for example, can already perform a firstanalysis of a fill level of a packing trough 40, 41 on the basis of thesignals received by the sensor units 601-610.

The third control unit 432 can also be integrated into the secondcontrol unit 431, for example. However, it is also conceivable andpossible to embody the third control unit 432 and the second controlunit 431 as separate units, which are connected to one another via asuitable connection, for example a data connection in the form of anetwork connection.

The third control unit 432 can, for example, perform a first analysis ofthe signals received by the sensor units 601-610. Results of this firstanalysis can be transmitted to the higher-order, second control unit431, which carries out a further analysis and communicates with thefirst control unit 430. The control unit 430 which controls thehigher-order system can then evaluate data which it receives from thesecond control unit 431, to control a conveyor belt system 2 as afunction thereof, for example. The control unit 430 can also trigger anadjustment of the product distributing guide 42, for example, whereinthe control of the movement procedure of the product distributing guide42, i.e., for example, an activation of a drive unit of the productdistributing guide 42, can be performed by the second control unit 431,to which the product distributing guide 42 is connected.

A scanning device 433, for example in the form of a product scanner 3(see FIG. 1), which in turn also communicates with the third controlunit 432, can be connected to the first control unit 430. For example,monitoring can be performed in this manner by interaction of thescanning device 433 with the sensor units 601-610. For example, if it isestablished that a product object 7 arrives in the region of a packingtrough 40, 41 (which can be established on the basis of a change of thefill level in this packing trough 40, 41), although no product object 7has been scanned at the scanning device 433, this can indicate anattempt at manipulation.

FIG. 12 shows an exemplary embodiment of an interconnection of differentsensor units 601-603.

The sensor units 601-603 can thus each have an assembly 65, whichcomprises the components required for the sensor function of the sensorunit 601-603, for example an emitter unit and/or a receiver unit. Thesensor units 601-603 are each embodied modularly and comprise input-sideterminals 650-654 and output-side terminals 655-658.

A power supply can be connected to the sensor units 601-603 via theinput-side terminals 650, 651, wherein the sensor units 601-603 areinterconnected in series, so that output-side terminals 657, 658 of onesensor unit 601, 602 are connected to input-side terminals 650, 651 ofthe next sensor unit 602, 603, to transmit a supply voltage toward thenext sensor unit 602, 603.

An interconnection of the sensor assemblies 65 of the sensor units601-603 can be performed in a cascaded form via the remaining terminals.Thus, a first sensor line, via which signals can be transmitted towardand away from the sensor assembly 65 of the first sensor unit 601, canbe connected to an input-side terminal 652 of the first sensor unit 601.A second sensor line, in contrast, is connected to a terminal 653 of thefirst sensor unit 601 and a third sensor line is connected to aninput-side terminal 654 of the first sensor unit 601.

The input-side terminal 653 of the first sensor unit 601 is wired to theoutput-side terminal 655 of the first sensor unit 601, which is in turnconnected to the input-side terminal 652 of the second sensor unit 602,so that via this, the second sensor line is connected to the sensorassembly 65 of the second sensor unit 602. The input-side terminal 654of the first sensor unit 601, in contrast, is connected to theoutput-side terminal 656 of the first sensor unit 601, which is in turnconnected to the input-side terminal 653 of the second sensor unit 602.This input-side terminal 653 of the second sensor unit 602 is wired tothe output-side terminal 655 of the second sensor unit 602, which isconnected to the input-side terminal 652 of the third sensor unit 603,so that the assembly 65 of the third sensor unit 603 is connected to thethird sensor line.

This cascaded form of the interconnection is fundamentally scalable asdesired, wherein for the cascaded connection of more than three sensorunits 601-603 to one another, more terminals are accordingly to beprovided on the individual sensor units 601-603. A star circuit of thetype shown in principle in FIG. 11 is implemented by the cascadedinterconnection, wherein the number of the cables to be laid can bereduced, because lines can be combined.

The concept on which the invention is based is not restricted to theabove-described exemplary embodiments, but rather may also beimplemented in entirely different ways.

A fill level recognition in the form described here is not restricted inprinciple to product checkout systems. For example, in reverse vendingmachines, for example for beverage containers, packing troughs can alsobe present, into which containers are conveyed and at which a fill levelrecognition can be performed according to the type described here.

The sensors are not necessarily embodied as infrared emitters and/orreceivers, but rather can also be designed differently. For example,ultrasonic sensors, capacitive sensors, inductive sensors, pressuresensors, cameras, or the like can also be used.

LIST OF REFERENCE SIGNS

-   1 product checkout system-   2 conveyor system-   20-24 conveyor device-   3 product scanner-   4 packing trough system-   40, 41 packing trough-   400-403 side-   42 product separation device-   420 pivot axis-   43 control device-   430-432 control units-   433 scanning device-   44 drive device-   5 payment terminal-   6 sensor device-   601-610 sensor unit-   611-614 sensor unit-   62, 632-637 reflection point-   64 display device-   7 object-   A1-A9 steps-   D pivot direction-   F conveyor device-   L, L′, L1, L1′, L2, L2′ light cone family-   P path-   S, S′ sensor signal-   S1-S6 signal path

1. A reception system for receiving objects, comprising at least onereception device for receiving objects, a conveyor device, which has atleast one conveyor belt section for conveying objects in a conveyancedirection into the at least one reception device, and a sensor device,which is arranged on the at least one reception device, for detectingobjects in the at least one reception device, wherein the sensor deviceis designed to emit sensor signals along different signal paths over thereception device, to conclude a fill level of the reception device onthe basis of an interaction of at least one of the sensor signals withobjects conveyed into the reception device.
 2. The reception signalaccording to claim 1, wherein the sensor signals are formed by signalsof infrared light.
 3. The reception system according to claim 1, whereinthe sensor device has one emitter for emitting sensor signals and aplurality of receivers for receiving the sensor signals or a pluralityof emitters for emitting sensor signals and one receiver for receivingthe sensor signals.
 4. The reception system according to claim 1,wherein the at least one reception device is bordered at least insections by wall sections, wherein sensor units are arranged spatiallyoffset on different wall sections of the at least one reception device.5. The reception system according to claim 1, wherein a first sensorunit, which forms an emitter, is arranged on a first wall section of theat least one reception device and the second sensor unit, which forms areceiver, is arranged opposite to the first sensor unit on a second wallsection opposite to the first wall section.
 6. The reception systemaccording to claim 1, wherein at least one sensor unit of the sensordevice is designed as a reflection sensor for emitting a sensor signaland for receiving a reflected signal.
 7. The reception system accordingto claim 6, wherein the sensor device is designed to determine adistance value of the at least one reflection sensor to a reflectedobject on the basis of a received reflected signal.
 8. The receptionsystem according to claim 6, wherein the at least one sensor unitdesigned as a reflection sensor is designed to determine, by comparisonof a signal level of a received reflected signal to different thresholdvalues, whether the reflected signal has been reflected by an object atshort range to the sensor unit or at long range to the sensor unit. 9.The reception system according to claim 1, wherein at least one sensorunit of the sensor device is designed as a reflection sensor foremitting a sensor signal and for receiving a reflected signal andadditionally for receiving an emitted signal of another sensor device.10. The reception system according to claim 1, wherein the receptionsystem has a control device for analyzing sensor data obtained on thebasis of the sensor signals, to conclude the fill level of the receptiondevice on the basis of the sensor data.
 11. The reception systemaccording to claim 10, wherein the control device is designed to controlthe conveyance speed of at least one conveyor belt section of theconveyor device as a function of an ascertained fill level.
 12. Thereception system according to claim 10, wherein the reception system hasan object separation device arranged on the conveyor device, which isadjustable to guide objects into different reception devices, whereinthe control device is designed to activate a drive device to adjust theobject separation device as a function of an ascertained fill level. 13.The reception system according to claim 1, wherein sensor units of thesensor device each have a display device for outputting visual displaysignals as a function of a fill level of the reception device.
 14. Thereception system according to claim 1, wherein a sensor unit, which isdesigned as an emitter, of the sensor device is designed to emit asensor signal, which contains an identification identifier and is usedas a test signal, for mutual identification, to at least one othersensor unit designed as a receiver.
 15. The reception system accordingto claim 14, wherein the sensor unit is designed to analyze the testsignal received at the sensor unit designed as a receiver and to comparethe signal level of the test signal to a stored reference value, toconclude a change at the sensor device on the basis of the comparison.16. A product checkout system or reverse vending machine having areception system according to claim
 1. 17. The method for operating areception system for receiving objects, in which at least one receptiondevice receives objects, in that a conveyor device having at least oneconveyor belt section conveys objects in a conveyance direction into theat least one reception device, and a sensor device arranged on the atleast one reception device detects objects in the at least one receptiondevice, wherein the sensor device emits sensor signals along differentsignal paths over the reception device, to conclude a fill level of thereception device on the basis of an interaction of at least one of thesensor signals with objects conveyed into the reception device.